<template>
  <view>
    <my-search @click="gotoSearch" ></my-search>
    <view class = "scroll-view-container">
      <!-- 左边滚动区域 -->
      <scroll-view class="left-scroll-view" scroll-y :style="{height : wh + 'px'}">
        <block v-for="(item, i) in cateList" :key="i">
          <view :class="['left-scroll-view-item', i === active ? 'active' : '']" @click.native="activeChanged(i)">{{item.cat_name}}</view>
        </block>
      </scroll-view>
      <!-- 右侧滚动视图 -->
      <scroll-view class="right-scroll-view" scroll-y :style="{height: wh + 'px'}" :scroll-top="scrollTop">
        <!-- 二级列表数据 -->
        <view class="cate-lv2" v-for="(item2, i2) in cateLevel2" :key="i2">
          <view class="cate-lv2-title">/{{item2.cat_name}}/</view>
          <!-- 三级列表数据 -->
          <view class="cate-lv3-list">
            <!-- 三级分类item项 -->
            <view class="cate-lv3-item" v-for="(item3, i3) in item2.children" :key="i3" @click="gotoGoodsList(item3)">
              <image :src="item3.cat_icon"></image>
              <text>{{item3.cat_name}}</text>
            </view>
          </view>
        </view>
        
      </scroll-view>
    </view>
  </view>
</template>

<script>
  export default {
    data() {
      return {
        wh:0,
        //分类数据表
        cateList:[],
        active:0,
        cateLevel2:[],
        scrollTop:0
      };
    },
    onLoad(){
      //获取当前系统信息
      const sysInfo = uni.getSystemInfoSync()
      //为wh窗口可用高度动态赋值
      this.wh = sysInfo.windowHeight - 50
      //调用获取分类表的方法
      this.getCateList()
    },
    methods:{
      async getCateList(){
        const {data:res}=await uni.$http.get('/api/public/v1/categories')
        if(res.meta.status!==200)return uni.$showMsg()
        
        this.cateList=res.message
        this.cateLevel2=res.message[0].children
      },
      activeChanged(i){
        this.active=i
        this.cateLevel2=this.cateList[i].children
        this.scrollTop = this.scrollTop===0?1:0
      },
      gotoGoodsList(item3){
        uni.navigateTo({
          url:'/subpkg/goods_list/goods_list?cid='+item3.cat_id
        })
      },
      gotoSearch(){
        uni.navigateTo({
          url:'/subpkg/search/search'
        })
      }
    }
  }
</script>

<style lang="scss">
.scroll-view-container{
  display: flex;
  .left-scroll-view{
    width:120px;
    .left-scroll-view-item{
      line-height: 60px;
      background-color: #F7F7F7;
      text-align:center;
      font-size:12px;
      //激活样式
      &.active{
        background-color: #FFFFFF;
        position: relative;
        &::before{
          content: ' ';
          display: block;
          width: 3px;
          height: 30px;
          background-color: #c00000;
          position: absolute;
          left:0;
          top:50%;
          transform:translateY(-50%);
        }
      }
    }
  }
  .cate-lv2-title{
    font-size: 12px;
    font-weight: bold;
    text-align: center;
    padding:15px 0;
  }
  .cate-lv3-list{
    display: flex;
    flex-wrap: wrap;
    .cate-lv3-item{
      width: 33.33%;
      margin-bottom: 10px;
      display: flex;
      flex-direction: column;
      align-items: center;
    }
    image{
      width: 60px;
      height: 60px;
    }
    text{
      font-size: 12px;
    }
  }
}
</style>
